When a Location-Based Services (LBS) application wishes to establish the location of a mobile station (MS) in a wireless network, the application may send a location request message to the wireless carrier that serves the MS. In response, the carrier may engage in a process to determine where the MS is currently located, and the carrier may then generate a response to the location request and send the response to the LBS application. To this end, the wireless carrier may operate a location server that acts as a front end for receiving location requests from the LBS application and forwarding those requests to a position determining system. Thus, when the location server receives a location request from the LBS application, the location server may send a corresponding location request to the position determining system, and the position determining system may, in turn, determine the location of the MS. The positioning system returns the determined location of the MS to the location server, which then returns to the LBS application the determined location or data derived from the determined location (such as mapping, routing, or street address information, for instance).
Oftentimes to determine the location of a MS, the position determining system will need to obtain location information from the MS itself. Depending on the capabilities of the MS, the location information that can be obtained from the MS may comprise satellite positioning data, such as global positioning system (GPS) readings or other data, information regarding the cell/sector in which the MS is currently operating, and information about signals the MS is receiving from various base stations, for instance. However, not all MSs are equipped with the same capabilities for generating location information. Moreover, some MSs are equipped with multiple modules capable of supplying location information but having different response and precision characteristics. Thus, it will be appreciated that methods previously used for communicating with a MS in order to obtain location information can be inadequate.